It does not allow the sending of messages and shows us a message indicating that it has exceeded the maximum number of messages sent per day. We have anti-spam mechanisms in place. These mechanisms are stricter in the mailings made from Webmail to avoid abuses as they are more exposed. A maximum of 300 messages can be sent and in total to a maximum of 300 recipients every 24 hours.

Up to 99 recipients can be placed in each message. However, from another computer in the UPM network or in Spain other than Webmail, this limit is wider and it is allowed to send 300 messages every 24 hours. And each of those messages can contain up to 99 recipients maximum.

Thus, they could be sent to a total of 30,000 recipients (300 messages x 99 recipients/message) in 24 hours. This check takes into account shipments in the last 24 hours (not calendar day). As the hours go by, messages sent 24 hours before are "released".

If the user needs to make a high number of sends, we advise that they use an email client and send from an IP in Spain or the UPM (using VPN if they are outside Spain).
A temporary increase in the number of messages every 24 hours can be authorised by means of the corresponding incident in PV managed through the centre's IT manager.
(User service -> Requests ->Relating to Mail -> Increase in the maximum number of email messages)
SMTP can block the user if these limits are exceeded